The invention relates to an exhaust-gas turbocharger for an internal combustion engine including a compressor disposed in an engine intake section and or turbine disposed in an engine exhaust section and having a plurality of exhaust gas inlet flows and a turbine bypass line and a rotary slide valve for controlling the exhaust gas flows through and past the turbine.
DE 196 18 160 C2 discloses an exhaust-gas turbocharger for an internal combustion engine, the turbine of which has a rotor and a turbine housing having at least two inlet flow passages which are separated by a separating wall, and a bypass branching off from at least one flow passage. Exhaust gas can be conducted away from at least one flow passage via this bypass. The bypass is configured in such a way that a section of the bypass is formed by the separating wall of the flows passages, this section having openings, in order to provide for, or to block, a flow connection from the bypass to at least one of the flow passages. A bypass valve is arranged in the section of the bypass which is formed by the separating wall. This bypass valve is provided with flow channels. The flow connection can then be produced via the bypass valve between one of the two flow passages or both flow passages at the same time and the bypass, in such a way that the flow channels in the valve are situated in partial or in complete congruence with the openings of the section in the separating wall of the bypass. That section of the separating wall which forms the bypass is configured as a cylindrical sleeve having the abovementioned openings, and the valve is configured as a rotary slide which is arranged in the cylindrical sleeve and has the abovementioned flow channels. The exhaust gas supply to the turbine can be metered accurately via the valve. The abovementioned openings are groove-shaped recesses in the wall of the rotary slide and not through-flow openings. The intention is to ensure the high mechanical requirements of the optional turbo-brake system (called turbo-brake) which has been put into series production in the meantime. One of the basic elements of the turbo-brake of a turbine having two or more flow passages is a turbo-brake radial flow guide structure which can be displaced axially directly in front of the turbine wheel and a two-flow blow-off device for diverting exhaust gas from the flow ducts or passages to the turbine. The turbo-brake radial flow guide structures are filigree precision casting die parts which are more expensive the higher the mechanical and thermal requirements are on account of high exhaust gas mass flows.
It is the object of the present invention to provide an exhaust-gas turbocharger for an internal combustion engine, which exhaust-gas turbocharger satisfies the mechanical and thermal requirements of modern turbo-brake systems.